I think negative reviews fall into specific categories, and there is no one answer for responding. Examples:
Girl advertises services, does not/will not provide, on something etc - if if EE origin I dont think a negaive would have any effect, so totally justified as warning to others. (But she'll change IDs)
Girl's service is lacking and mediocre - depending on the degree of crapness, some may think a neg is harsh, but may act as a wake up call to the girl. Only she knows if she cares enough to up her game so as to avoid further negs through own complacency.
Girl is crap, poor customer service skills/attitude problem - give her a neg, and she'll give the punter a neg back. A tit-for-tat situation, BUT, the WG can do the punter's reputation far more damage, particularly if she lies in her response.
At lot of the problems fall down to poor comms and misunderstandings, but I'd conceed that a lot of girls are unaware that they are marketing themselves as a commoddity, so to speak, and simply do not have or understand the attributes for good customer service.
In business, every company (should) want the customer to return, so as to build business and be successful, and they follow up with phone or web-based surveys. Some years back a car dealer called me after a service to ask if I was satisfied. I said no I was not, as the car had not been washed and worse, the service book, which was on the front seat had not been stamped. I told service lady that this was plain sloppy and also I questioned whether the car had been in the workshops (I had checked and found clean oil, but thought I'd piss them off). Grovelly apology, no offer of a partial refund, only bring it in for a wash. Too late, damage done, customer lost. Contrast that to another car that developed a major engine fault under warranty. Taken in, stripped, fixed, washed/hoovered, provided courtesy car, full explanation of fault and work done, with a follow up call a week later to check all was OK. It's not difficult.
My experience with WGs shows that there are a small percentage to not only enjoy what they do but work hard and care enough to make sure the paying customer walks away with a smile on his face - and are very likely to return. Then there are the others who dont give a toss but are happy for the cash, and another small percentage, who are out and out scammers.
It's a brave WG who would publicly admit that following a negative report, that the punter was right, the report justifield and she's taking steps to improve.
It's why the Amera's, Little Honey Jessica's, Emily Janes, Miss KDDs etc, etc are so successful - they go the extra mile for the paying client. Why do some women find that so hard to do? Maybe they should jack it in and get a job stacking supermarket shelves?